Junior — Middle
Have you had experience working with composite indexes in a database?
sobes.tech AI
Answer from AI
Yes, I have experience working with composite indexes in databases. A composite index is an index created on multiple columns of a table simultaneously. It helps to speed up queries that filter or sort data based on multiple fields.
For example, in SQL, you can create a composite index like this:
CREATE INDEX idx_user_lastname_firstname ON users (last_name, first_name);
This index is useful for queries that use conditions on both last_name and first_name at the same time, for example:
SELECT * FROM users WHERE last_name = 'Ivanov' AND first_name = 'Ivan';
It is important to remember that the order of columns in a composite index affects its usage. The index works efficiently for queries starting with the first column of the index.